Conventional electrophotographic image-forming devices, such as laser printers, have been provided with process cartridges accommodating a developer and capable of being detachably mounted in the image-forming devices.
This type of process cartridge is partitioned into a developer-accommodating section and a developing section. An agitator provided in the developer-accommodating section is driven to rotate in order to agitate and convey developer into the developing section. The developing section is provided with a developing roller and a supply roller that oppose and contact each other, and a thickness-regulating blade that contacts the surface of the developing roller with pressure.
When the process cartridge is mounted in the laser printer, a gear mechanism or the like inputs a driving force from the laser printer into the process cartridge to rotate the agitator. As a result, the agitator conveys developer from the developer-accommodating section to the developing section. The rotating supply roller in the developing section then supplies this developer onto the developing roller. At this time, the developer is tribocharged between the supply roller and the developing roller. As the developing roller rotates, the developer supplied onto the surface of the developing roller passes beneath the thickness-regulating blade so that a thin layer of uniform thickness is carried on the surface of the developing roller.
This type of process cartridge is mounted in the laser printer so that the developing roller in the cartridge opposes a photosensitive drum in the laser printer. When the thin layer of developer carried on the surface of the developing roller rotates opposite the photosensitive drum, an electrostatic latent image formed on the surface of the photosensitive drum is developed into a toner image. The toner image is subsequently transferred onto a sheet of paper by a transfer roller, thereby forming an image on the paper.
Through repeated use of this process cartridge mounted in the laser printer, developer accommodated in the developer-accommodating section is consumed until the cartridge runs out of toner. At this time, the laser printer displays an out-of-toner message, prompting the user to replace the process cartridge. Accordingly, the user removes the used process cartridge and mounts a new process cartridge in its place.
However, there has been an increasing trend recently to recycle used process cartridges rather than discarded them. In other words, the used process cartridges are refilled with developer and reused.
In order to recycle this type of process cartridge, the user must return the used process cartridge to the manufacturer or to a prescribed recycling factory. Further, the manufacturer or the recycling center must extract any developer remaining in the developer-accommodating section of the used process cartridge to a sufficient degree that old residual developer will not affect the reuse of the process cartridge after the process cartridge has been refilled with new developer.
Various methods for packing new process cartridges have been considered in the past. For example, one method proposed in Japanese Patent Application Publication No. 2001-278342 employs a package including a casing filled with polymerized toner used for image formation, and a packing material for packing the casing so that the casing has a different vertical orientation than during use. More specifically, the casing is packed in the packing material in a state inverted to the state during use. Accordingly, when the user unpacks the casing and mounts the casing at a proper orientation in an image-forming device, the process of inverting the casing from the orientation used during packing eliminates settling and coagulation of the polymerized toner accumulated on the ceiling portion of the casing that may have occurred due to gravity and vibration during transport, thereby reliably loosening up the toner.